99% sensitive and 98% specific to support accuracy of negative and positive ROM clinical results

The AmniSure ROM (Rupture Of [fetal] Membranes) Test is a rapid, non-instrumented, qualitative immunochromatographic test for the in vitro detection of amniotic fluid in vaginal discharge of pregnant women. The AmniSure ROM Test uses amniotic test strips to detect the PAMG-1 protein marker of the amniotic fluid in vaginal discharge. The amniotic fluid test is used by health care professionals to aid in the detection of ROM in pregnant women reporting signs, symptoms, or complaints suggestive of ROM.

Premature rupture of fetal membranes (PROM) occurs in about 10% of pregnancies and poses one of the most important therapeutic dilemmas in current obstetric practice(2). Management of patients with PROM and pPROM (pre-term PROM, occurring before 37 weeks gestation) is expensive and remains an important perinatal dilemma as the clinician attempts to balance the risk of prolonging gestation against the risks of infection(2).

Risks of PROM at term are related to serious neonatal consequences such as pre-term delivery, fetal distress, prolapsed cord, abruptio placentae and infection(2). pPROM accounts for 20% to 40% of PROM cases, and is associated with 20% to 50% of premature births. Complications of pPROM include infectious morbidity in the mother and fetus, pulmonary hypoplasia of the fetus, prolapse of the umbilical cord, development of fetal deformities, and postnatal endometritis(2). All of these consequences significantly increase risk of fetal and maternal morbidity and mortality.

The AmniSure ROM Test kit is a self-contained system that serves as an aid to rapidly and accurately diagnosis PROM, which is crucial to ensure appropriate obstetric measures are taken in the event of a rupture. Failure to identify patients with ROM can result in the failure to intervene appropriately.

Conversely, the false diagnosis of ROM can lead to inappropriate interventions (e.g., hospitalization or induction of labor). Therefore the correct and timely diagnosis of ROM is of crucial importance for the clinician(2). Accurate diagnosis of [fetal] membranes rupture, however, remains a frequent clinical problem in obstetrics(2-4).

Other available tests have limitations or are in some degree invasive(2). The AmniSure ROM Test is a rapid, non-invasive, amniotic fluid test that can aid in the detection of ROM, providing rapid, easy-to-interpret and timely results. As an alternative to conventional methods of ROM detection, the AmniSure test has a 99% sensitivity and 98% specificity to support accuracy of negative and positive ROM clinical results.

Principle

The AmniSure ROM Test uses the principles of immunochromatography to detect human PAMG-1 protein present in amniotic fluid. The test employs highly sensitive monoclonal antibodies that detect even a minimal amount of PAMG-1, which is present in cervicovaginal discharge after rupture of fetal membranes. PAMG-1 was selected as a marker of fetal membranes rupture due to its high level in amniotic fluid, low level in blood, and extremely low background level in cervicovaginal discharge when fetal membranes are intact. To minimize the frequency of false results, two monoclonal antibodies were selected to set the sensitivity threshold of the AmniSure ROM Test at the optimal low level of 5 ng/ ml.The maximum background concentration of PAMG-1 in cervicovaginal discharge is slightly lower than the sensitivity cut-off of the AmniSure ROM Test, reducing false results and allowing for ~99% accuracy(2). A sample of cervicovaginal discharge (collected by vaginal swab) is placed into a vial with solvent for extraction. PAMG-1 is then detected in the sample through an amniotic fluid test strip (lateral flow device). The result is read visually by the presence of one or two lines in the test region of the strip.

Procedure

The simple 4-step test procedure* detects placental alpha microglobulin-1 (PAMG-1) a protein found in high concentrations in amniotic fluid and low concentration in cervicovaginal fluid (4).

Insert amniotic fluid test strip into vial and remove if 2 lines are visible, or at 5 minutes sharp.

Results are observed and recorded.

*Please refer to package insert for complete instructions for use.

Applications

The AmniSure test is for use by healthcare professionals to aid in the detection of fetal membranes rupture in pregnant women when they report signs, symptoms, or complaints suggestive of such a rupture. AmniSure should be used in appropriate sites by qualified personnel (physicians, certified nurse-midwives, or labor and delivery nurses certified to evaluate ROM). AmniSure can therefore be used in a variety of settings, from OB/GYN clinics and doctors’ offices, to outpatient clinics and labor admitting rooms.